Peptide-Functionalized Dendrimer Nanocarriers for Targeted Microdystrophin Gene Delivery

Area of Science:

• Biotechnology
• Nanomedicine
• Gene Therapy

Background:

• Gene therapy faces challenges in in vivo delivery, including cellular uptake and nuclear transport.
• Duchenne muscular dystrophy (DMD) is a debilitating genetic disorder requiring effective therapeutic strategies.

Purpose of the Study:

• To develop a targeted nanocarrier for efficient delivery of the microdystrophin gene to skeletal muscle cells.
• To overcome limitations in intracellular trafficking and nuclear membrane transport for gene therapy applications.

Main Methods:

• A modified G5 polyamidoamine (G5 PAMAM) dendrimer was engineered with specific peptides (SMTP, DBP, NLS) for targeted delivery.
• The nanocarrier was polyplexed with plasmid DNA encoding GFP-tagged microdystrophin (µDys) and characterized for stability, size, charge, and cytotoxicity.
• In vitro transfection efficiency and in vivo protein expression were evaluated in cell cultures and Duchenne model mice (mdx^4Cv).

Main Results:

• Optimized G5 PAMAM nanocarrier polyplexes demonstrated successful in vitro transfection, leading to GFP and µDys protein expression.
• In vivo studies in mdx^4Cv mice confirmed protein expression, indicating effective gene delivery to skeletal muscle.
• The nanocarrier system showed stability and acceptable cytotoxicity profiles.

Conclusions:

• The developed peptide-modified G5 PAMAM dendrimer nanocarrier facilitates targeted gene delivery of microdystrophin to skeletal muscle cells.
• This approach holds potential for improving muscle function in patients with Duchenne muscular dystrophy.
• The study highlights the efficacy of targeted nanocarriers in overcoming gene delivery barriers for genetic disorders.